He's from Peru; she's from Jamaica. They met in Miami while working for Arquitectonica, the boundary-pushing, color-loving modern architecture firm. Working together led Claudine and Giorgio Lostao to love and then to marriage, children (Luca, now 5, and Mila, 3), six renovated homes, a cross-country move and now their own firm, Ridiculous Design -- as in something that is so cool-looking it's ridiculous! Not that their motivations aren't serious: They moved to Portland because of the city's high green profile and then found that their house -- 3,700 square feet with many gigantic bedrooms -- was just too big (a lesson in green living).

"People would come over and love the old house," Claudine says, "but we hated it." Her close-knit family felt disconnected there. Like the other places they designed for themselves, the big house was sold furnished -- which made moving a lot easier. The young family arrived in their new home with just their clothes and books.

The 1940s house they bought, in the tradition-bound Council Crest neighborhood, consisted of nearly 1,900 square feet on two levels. It needed help, but recycling an existing building was part of the Lostaos' larger life plan. They gutted the original house and added 1,000 square feet that contains the new kitchen, family room and master suite. Although neighbors met the modernist project with trepidation, the Black + White House has since won them over.

Now the master bedroom (upstairs in the new wing) is roomy without being too big. To encourage togetherness, Claudine and Giorgio designed the bedroom as an additional family gathering place, with a corner sectional sofa (from West Elm) and a massive coffee table -- or as a place for Mom and Dad to hang out when Mila and Luca have commandeered the living room TV.

The master suite also demonstrates the couple's mix-and-match approach to modern and traditional design elements. A contemporary low-lying Tokyo bed by Piero Lissoni for Porro has storage drawers hidden in the base. It's up against a mural that looks like a drop from an old stage set (she sewed it, he painted it). It's certainly a quick way to add a fireplace to a room, and it's the perfect transitional element tying the modern furniture to the antique dentist's cabinet (which shows off a pair of miniature chairs from Vitra). The metal barn door, which opens onto the stair landing (with the closet and master bathroom directly across), not only economizes on space but adds an industrial touch. "We wanted to keep things raw," Giorgio says. "There's a beauty in materials when they develop a patina."

The children's rooms are on the lower floor, which was a concern for their mother. Luckily the new light shafts the Lostaos incorporated into their design also provide auditory connections. "At first I was worried about being on two different levels," says Claudine, "but it works. Mila can just call to me and say, 'Mom, is it time to wake up?' I don't even use a monitor."

Besides the bright-yellow accent walls and through line of industrial materials, the Lostaos' home is defined by transparency. In the master bath, the couple created a series of glass-walled partitions demarking their clothes closet, shower and commode (there are curtains, too, for privacy). "It's ridiculous," says Claudine (invoking the name of her firm), "to expose something people keep behind closed doors. But we thought it would be fun."

Fun is something you would expect from a couple who named their company Ridiculous Design. And the house is full of quotes from favorite films painted on the walls and glass partitions. They're not the cozy adages you might expect but are of a generally edgier, appropriately off-kilter variety, like the bathroom's selection from Zoolander, which asks, "Have you ever wondered if there was more to life, other than being really, really ridiculously good-looking?"

Ridiculous Design operates in the Lostaos' office-studio, which they installed in the home's bonus room. "Giorgio and I are together 24 hours a day," Claudine says, "but it works for us. We're a good balance. I tend to be more conservative, and he tends to be more loose and out there."

Meanwhile, no worries about the house that had neighbors fearing a modern-architecture invasion. The Lostao place has drawn mostly rave reviews. "Our neighbor Sue, who is 90, is our biggest fan," Claudine laughs. "She says she lives next to a piece of art."

What the Pros Know

"Too often," says Giorgio Lostao, "residential projects don't have good natural light." There's a tendency in houses to overglaze in certain spots and underilluminate others, he says. This creates an almost chiaroscuro effect to which the eyes must constantly readjust. "If you can get cross light that cuts through, front to back, and then up and down, that's the best," Claudine explains. So in marrying the addition to the renovated original house, the architects specified big expanses of windows, added fenestration in unexpected places (like the foyer), and wrapped the staircase in glass to keep the light flowing between floors. To create the even field of light they desired, the Lostaos worked with Petrina Construction, a local firm new to contemporary design, to incorporate a commercial window system into the house: A large gridded bank of high-efficiency, aluminum-framed storefront windows now wraps around the southeast corner of the home's ground floor.